https://gcc.gnu.org/g:9bd0b709ddb70589436c326142b1566f49f5e979
commit r15-621-g9bd0b709ddb70589436c326142b1566f49f5e979
Author: Viljar Indus <in...@adacore.com>
Date: Wed Mar 13 11:24:59 2024 +0200
ada: Improve deriving initial sizes for container aggregates
Deriving the initial size of container aggregates is necessary
for deriving the correct capacity for bounded containers.
Add support for deriving the correct initial size
when the container aggregate is iterating over an array
object.
gcc/ada/
* exp_aggr.adb (Expand_Container_Aggregate):
Derive the size for iterable aggregates in the case of
one-dimensional array objects.
Diff:
---
gcc/ada/exp_aggr.adb | 83 ++++++++++++++++++++++++++++++++++------------------
1 file changed, 55 insertions(+), 28 deletions(-)
diff --git a/gcc/ada/exp_aggr.adb b/gcc/ada/exp_aggr.adb
index 892f47ceb050..2476675604cc 100644
--- a/gcc/ada/exp_aggr.adb
+++ b/gcc/ada/exp_aggr.adb
@@ -6693,9 +6693,9 @@ package body Exp_Aggr is
-- If one or more of the associations is one of the iterated
-- forms, and is either an association with nonstatic bounds
- -- or is an iterator over an iterable object, then treat the
- -- whole container aggregate as having a nonstatic number of
- -- elements.
+ -- or is an iterator over an iterable object where the size
+ -- cannot be derived, then treat the whole container aggregate as
+ -- having a nonstatic number of elements.
declare
Has_Nonstatic_Length : Boolean := False;
@@ -6725,37 +6725,43 @@ package body Exp_Aggr is
Comp := First (Component_Associations (N));
while Present (Comp) loop
- Choice := First (Choice_List (Comp));
+ if Present (Choice_List (Comp)) then
+ Choice := First (Choice_List (Comp));
- while Present (Choice) loop
- Analyze (Choice);
+ while Present (Choice) loop
+ Analyze (Choice);
- if Nkind (Choice) = N_Range then
- Lo := Low_Bound (Choice);
- Hi := High_Bound (Choice);
- Add_Range_Size;
+ if Nkind (Choice) = N_Range then
+ Lo := Low_Bound (Choice);
+ Hi := High_Bound (Choice);
+ Add_Range_Size;
- elsif Is_Entity_Name (Choice)
- and then Is_Type (Entity (Choice))
- then
- Lo := Type_Low_Bound (Entity (Choice));
- Hi := Type_High_Bound (Entity (Choice));
- Add_Range_Size;
+ elsif Is_Entity_Name (Choice)
+ and then Is_Type (Entity (Choice))
+ then
+ Lo := Type_Low_Bound (Entity (Choice));
+ Hi := Type_High_Bound (Entity (Choice));
+ Add_Range_Size;
- Rewrite (Choice,
- Make_Range (Loc,
- New_Copy_Tree (Lo),
- New_Copy_Tree (Hi)));
+ Rewrite (Choice,
+ Make_Range (Loc,
+ New_Copy_Tree (Lo),
+ New_Copy_Tree (Hi)));
- else
- -- Single choice (syntax excludes a subtype
- -- indication).
+ else
+ -- Single choice (syntax excludes a subtype
+ -- indication).
- Siz := Siz + 1;
- end if;
+ Siz := Siz + 1;
+ end if;
- Next (Choice);
- end loop;
+ Next (Choice);
+ end loop;
+
+ elsif Nkind (Comp) = N_Iterated_Component_Association then
+
+ Siz := Siz + Build_Siz_Exp (Comp);
+ end if;
Next (Comp);
end loop;
end if;
@@ -6770,6 +6776,7 @@ package body Exp_Aggr is
function Build_Siz_Exp (Comp : Node_Id) return Int is
Lo, Hi : Node_Id;
Temp_Siz_Exp : Node_Id;
+ It : Node_Id;
begin
if Nkind (Comp) = N_Range then
@@ -6835,8 +6842,28 @@ package body Exp_Aggr is
end if;
elsif Nkind (Comp) = N_Iterated_Component_Association then
- return Build_Siz_Exp (First (Discrete_Choices (Comp)));
+ if Present (Iterator_Specification (Comp)) then
+
+ -- If the static size of the iterable object is known,
+ -- attempt to return it.
+
+ It := Name (Iterator_Specification (Comp));
+ Preanalyze (It);
+ -- Handle the simplest cases for now where It denotes a
+ -- top-level one-dimensional array objects".
+
+ if Nkind (It) in N_Identifier
+ and then Ekind (Etype (It)) = E_Array_Subtype
+ and then No (Next_Index (First_Index (Etype (It))))
+ then
+ return Build_Siz_Exp (First_Index (Etype (It)));
+ end if;
+
+ return -1;
+ else
+ return Build_Siz_Exp (First (Discrete_Choices (Comp)));
+ end if;
elsif Nkind (Comp) = N_Iterated_Element_Association then
return -1;
